(1) Field of the Invention
The invention concerns a method of and apparatus for determining geometrical dimensions of a vehicle wheel, in particular of a wheel rim.
(2) Description of Related Art
An apparatus which is known from U.S. Pat. No. 3,877,505 has a wheel receiving device to which the rim of a motor vehicle wheel can be fixed. The wheel receiving device can be rotated during the fitting or removal operation by means of a rotary drive device, for example an electric motor. The tyre can be fitted to the rim or released from the rim by means of fitting or removal tools. Provided on the removal tool is a sensing device in the form of a projection which senses the radial outside surface (rim bed) of the rim and which comprises a material which does not damage the rim material, for example plastic material. That ensures that the removal tool is kept at a given spacing from the surface of the rim in the removal operation. That prevents the rim surface being damaged by the hard material of the removal tool. In that case however there is the danger that the projection which senses the rim contour and which maintains the spacing wears away due to abrasion or is damaged in some other fashion.
It is also known from DE 25 29 343 B2 for the fitting or removal tool to be moved along a control surface which ensures that the tool is guided on a curved path along the rim contour in the rim bed during the fitting or removal operation. Here too there is the danger that the guidance along the desired curved path is no longer achieved due to abrasion wear at the control surface. The control surface therefore has to be frequently replaced.
U.S. Pat. No. 5,054,918 discloses a structured light scanning system that determines structural features of a vehicle wheel by analysing the reflected light from a stripe where a planar light beam impinges the body of the vehicle wheel.